I want to understand how previews and thumbnails work in OC8.
It seems to me the previews is a feature of OC core and gallery plus is just using it.
So I don't have any previews configuration in my config.php so defaults are used. Here are my observations.
Max preview size is set to 2048, so upon viewing pictures in a gallery, all images are scaled to 2048 and saved in "thumbnails" folder. So let's say my original pictures are 3000 by something pixels, I'll have them duplicated in thumbnails, scaled down to 2048. Now when viewing particular picture, for some reason the original picture is not served, instead another copy is created, scaled to 2000 by something. So now I have my original picture (3000 by something), thumbnail (2048 by something) and another thumbnail (2000 by something). What is the idea behind this?
I would expect thumbnails of certain size (e.g. 200x200) to be used when viewing a directory of pictures and the full size picture shown when particular picture is selected. So the thumbnails 2048x and 2000x seem redundant to me.
I tried to configure preview_max_x and preview_max_y but it seems to affect the actual size of picture served when viewing the particular picture (not just the preview of pictures in a folder).